Increasingly, business data processing systems, entertainment systems, and personal communications systems are implemented by computers across networks that are interconnected by internetworks (e.g., the Internet). The Internet is rapidly emerging as the preferred system for distributing and exchanging data. Data exchanges support applications including electronic commerce, broadcast and multicast messaging, videoconferencing, gaming, and the like.
The Internet is a collection of disparate computers and networks coupled together by a web of interconnections using standardized communications protocols. The Internet is characterized by its vast reach am a result of its wide and increasing availability and easy access protocols. Unfortunately, the ubiquitous nature of the Internet results in variable bandwidth and quality of service between points. The latency and reliability of data transport is largely determined by the total amount of traffic on the Internet and so varies wildly seasonally and throughout the day. Other factors that affect quality of service include equipment outages and line degradation that force packets to be rerouted, damaged and/or dropped. Also, routing software and hardware limitations within the Internet infrastructure may create bandwidth bottlenecks even when the mechanisms are operating within specifications.
Internet transport protocols do not discriminate between users. Data packets are passed between routers and switches that make up the Internet fabric based on the hardware's instantaneous view of the best path between source and destination nodes specified in the packet. Because each packet may take a different path, the latency of a packet cannot be guaranteed and in practice varies significantly. Likewise, data packets are routed through the Internet without any prioritization based on content.
Prioritization has not been an issue with conventional networks such as local area networks (LANs) and wide area networks (WANs) because the average latency of such networks has been sufficiently low and sufficiently uniform to provide acceptable performance. However, there is an increasing demand for network applications that cannot tolerate high and variable latency. This situation is complicated when the application is to be run over the Internet where latency end variability in latency are many times greater than in LAN and WAN environments.
A particular need exists in environments that involve multiple users accessing a network resource such as a web server. Examples include broadcast, multicast and videoconferences as well as most electronic commerce (e-commerce) applications. In these applications it is important to maintain a reliable connection so that the server and clients remain synchronized end information is not lost.
In e-commerce applications it is important to provide a satisfying buyer experience that leads to a purchase transaction. To provide this high level of service, a web site operator must ensure that data is delivered to the customer in the most usable and efficient fashion. Also, the web site operator must ensure that critical data received from the customer is handled with priority.
While efforts are continually being made to increase the capacity and quality of service afforded by the Internet, it is contemplated that congestion will always impact the ability to predictably and reliably offer a specified level of service. A need exists for a system to exchange data over the Internet that provides a high quality of service even during periods of congestion.